Minimization of drive tests (Minimization of Drive Tests, MDT) is classified into immediate MDT (immediate MDT) and logged MDT (logged MDT). In a logged MDT solution, a network side performs MDT configuration on a user equipment (User Equipment, UE) when the radio resource control (Radio Resource Control, RRC) is in a connected status; when the UE turns to an idle (idle) status, the UE performs MDT measurement and logging, and reports a logged MDT measurement result to the network side when the UE turns to the connected status. The reporting process is usually as follows: first, the UE reports indication information to the network side to indicate that the UE has logged MDT log data; second, when the network side needs to trigger the UE to report the MDT log data, the network side sends a request message to the UE; finally, after receiving the request message, the UE reports the logged MDT log data to the network side.
When the UE traverses public land mobile networks (Public Land Mobile Network, PLMN), before the UE reports the indication information described above or reports the MDT log data, the UE needs to determine whether a current registration PLMN (Registration PLMN, RPLMN) is the same as an MDT PLMN, where the MDT PLMN is the RPLMN of the UE when the MDT is configured; only when the current registration PLMN is the same as the MDT PLMN, the above reporting may be performed.
In another scenario, when a radio link failure (Radio Link Failure, RLF) or handover failure (Handover Failure, HOF) occurs on the UE, the UE logs an RLF or HOF report, and logs the RPLMN when the RLF or HOF occurs. In this scenario, the reporting process of the UE is usually as follows: first, the UE reports indication information to the network side to indicate that the UE has logged the RLF or HOF report; second, when the network side needs to trigger the UE to report the RLF or HOF report, the network side sends a request message to the UE; finally, after receiving the request message, the UE reports the logged RLF or HOF report to the network side. Similar to a logged MDT scenario, before reporting the indication information or submitting the report, the UE needs to determine whether the current RPLMN is the same as the RPLMN when the occurrence of the RLF or HOF is logged; and only when they are the same, the above reporting may be performed.
As seen from the above description, what is logged by the UE in the prior art is the RPLMN; however, when the UE fails to access a PLMN, a logging error or a reporting error occurs if what is logged is still the RPLMN. For example, assuming that the UE camps on a cell of a PLMN1 in the beginning and the RPLMN=PLMN1, after the UE moves from the PLMN1 to a PLMN2, the UE attempts to establish an RRC connection with a cell of the PLMN2; at this time, if the RRC connection fails to be established, the UE cannot access the PLMN2. At this time, because the UE does not access the PLMN2, the RPLMN of the UE cannot be updated and is still the PLMN1; if the UE still logs the RPLMN of the UE when the failure occurs, the PLMN1 is logged as a PLMN with a failed access and a report logging the failed access is still reported to the PLMN1; obviously, a logging error occurs and the cell of the wrong PLMN is reported to.